Which is bigger, the Seiko Prospex Sea or the Hemel HD24 Automatic?

The Seiko Prospex Sea wears larger at 42mm versus 40mm for the Hemel HD24 Automatic — a 2mm difference across the dial.

Which has better water resistance, the Seiko Prospex Sea or the Hemel HD24 Automatic?

The Seiko Prospex Sea is rated to 300m versus 200m for the Hemel HD24 Automatic.

Which has a longer power reserve, the Seiko Prospex Sea or the Hemel HD24 Automatic?

The Seiko Prospex Sea carries a 72-hour power reserve against 40 hours on the Hemel HD24 Automatic.

What movement does the Seiko Prospex Sea run compared to the Hemel HD24 Automatic?

Both watches run automatic movements — the Seiko Prospex Sea uses the 6R54 and the Hemel HD24 Automatic uses the Seiko NH38A.

Side by side

Seiko Prospex SeavsHemel HD24 Automatic

The numbers, the dial colors, the calibers — laid out so you can stop flipping between tabs.

Seiko Prospex Sea

hbc001j1

Hemel HD24 Automatic

the-gallant

MSRP $300

At a glance

13 of 29 specs differ

Diameter

Prospex Sea42mm

HD24 Automatic40mm

Power Reserve

Prospex Sea72h

HD24 Automatic40h

Water Resistance

Prospex Sea300m

HD24 Automatic200m

MSRP

Prospex Sea—

HD24 Automatic$300

Full specifications

Case

5 specs

Diameter

42mm

40mm

Thickness

13.3mm

13mm

Lug-to-Lug

48.6mm

48mm

Material

Stainless Steel

316L Stainless Steel

Water Resistance

300m

200m

Crystal & Dial

4 specs

Crystal

Sapphire

Domed Sapphire

AR Coating

Anti-reflective coating on inner surface

Inner

Dial Color

Black

Gallant USAF Edition

Lume

LumiBrite on hands, index(es) and bezel

None

Movement

3 specs

Caliber

6R54

Seiko NH38A

Power Reserve

72h

40h

Jewels

Pricing

1 specs

MSRP

—

$300

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Seiko Prospex SeavsHemel HD24 Automatic

At a glance

Full specifications

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